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Thursday, July 20, 2017

Solutions for Recording Studio Ground Hum and Noise

Noise and hum can be issues whenever you have multiple
pieces of gear and cables connecting them across rooms.There are many products to help reduce this
and a lot of advice on how to connect things to avoid these types of
problems.I recently was discussing this
with a friend, Brian Stoller, and he had a solution that I tried and it worked
with minimal time and cost!!!

In the new space, I had wired up everything and found that
there was a loud, noticeable hum on the speakers when I turned everything
on.The 60 Hz hum is caused by “ground
loops” where there are different grounds coming together through a cable from
one piece of equipment to another.In my
case, it was the ground from the mixing console to the power amp.If I unplugged the outputs on the mixer, my
hum went away.For large areas that cover multiple rooms, there are many write-ups on star-point grounding. These methods can also be applied to multiple cabinets and equipment within a room.

I remembered from a recent email chain from my friend Brian
where he had mentioned that in his multi-cabinet modular setup, he actually
measured voltage differences between the chassis/case/rails of his different
cabinets, sometimes upwards of a few volts!!!He ran some copper wire between the different cases and his power issues
were solved.

I ended up putting a wire in between the
screw and equipment on each and every rack rail and connecting/chaining these
together so all the rails of my various rack mounts were at the same
potential/voltage.This made all the
chassis grounds in all of my rack mount equipment (including the power supply
to my mixing console) tie together.I have
never heard my studio sound this quiet!This approach solved many of my noise issues that I had ignored and
lived with and only cost a spool of wire.I used stranded, tinned, 14 gauge copper wire.